Extend improve way accuracy mode to allow unglueing of nodes from other ways

[Woazboat]

Add a key modifier combination to the improve way accuracy mode that 'unglues' the currently active node that is closest to the cursor from other ways before moving it to the clicked position. (Similar to the effect of using the G - UnGlue Ways action with the way and the affected node selected)

This could immensely simplify and speed up the process of separating landuse that has been glued to roads. It would generally be a more ergonomic method for the vast majority of uses of the 'unglue' action since in most cases users unglue a node in order to be able to move it without affecting other ways. With this enhancement, this multi-step process would be reduced to a single click per node (of the same way) without having to constantly select nodes and pressing G.

[GerdP]

process of separating landuse that has been glued to roads.

My preferred way to do this is to use draw a line that goes next to the road, connect it to the landuse and use Alt+X, if useful I also remove useless nodes from the road.
With your proposed method one would probably get more nodes than needed for the multipolygon as well as the road.

[Woazboat]

POC: ​https://github.com/Woazboat/josm/tree/improve_way_unglue